Mom's marijuana winds up in breast milk

April 10, 2018 by Serena Gordon, Healthday Reporter

(HealthDay)—Breast-feeding has known benefits for both baby and mom, but if a new mom also smokes marijuana, does the drug turn up in her breast milk?

Yes, says new research. But the exact consequences of the small amount of that makes it to a baby aren't yet clear.

"This study is just a start to see if marijuana transferred into breast milk. Levels in milk were quite low," said senior study author Thomas Hale, director of the Infant Risk Center at Texas Tech University School of Medicine in Amarillo.

The researchers also don't know if the levels of pot in breast milk would rise if a woman smokes more.

Still, study co-author Dr. Teresa Baker, co-director of the Infant Risk Center at Texas Tech, said, "We do not recommend the use of marijuana. There's concern for the developing brain exposed to THC [the active component in marijuana]."

Both Hale and Baker said that should abstain from while breast-feeding because there's simply no known safe amount.

The study included eight women who used pot. The women lived in Denver, where is legal. Their use of marijuana varied, with most using the drug infrequently, although one woman said she'd used it seven to 10 times during the past week.

The women were between two and five months after delivery, and all were exclusively breast-feeding their babies.

The study was done completely anonymously. The researchers never knew who the women were.

The participants picked up a breast milk collection kit at a local community center. The kit included bottles for collecting breast milk as well as a new glass pipe for smoking marijuana to avoid contamination from past drugs used in a pipe.

The women were instructed to buy a specific strain of marijuana from a specific dispensary, so that they would all get a consistent dose of THC. The women were asked to stop smoking marijuana for 24 hours prior to smoking for the breast milk test.

After smoking for the test, mothers collected samples of breast milk at one, two and four hours after smoking.

About 2.5 percent of the amount the mother smoked was found in the breast .

Dr. Ronald Marino, chief of the division of general pediatrics at NYU Winthrop Hospital in Mineola, N.Y., reviewed the findings.

"Most things do get into , and we need to understand this more because we don't know if there's a safe exposure level for babies. But it's probably better not to be exposed," Marino said.

"Your baby's brain is developing so much in the first year of life, you want to give them every chance to have high function. Try to stay as pure as you can when breast-feeding—[avoiding] marijuana, alcohol or even herbal remedies," he added.

Marino said he didn't think this would be more of an issue in states with legalized recreational marijuana. "Marijuana has been legalized in many states, but so is alcohol. We know that just because alcohol is legal, it doesn't mean it's a reasonable thing to use when pregnant or -feeding."

Both Hale and Baker said more research is necessary because there are still many unanswered questions. This study only looked at inhaled marijuana—what about marijuana that's eaten? Would heavy users have different levels from occasional users? And the most important question: What exactly is the effect on the baby?

The study was published April 9 in the journal Obstetrics and Gynecology.

Explore further: Recent study in Oregon reveals public considers alcohol more harmful than marijuana

More information: Thomas Hale, Ph.D., professor and director, Infant Risk Center, Texas Tech University School of Medicine, Amarillo; Teresa Baker, M.D., associate professor, obstetrics and gynecology, and co-director, Infant Risk Center, Texas Tech University School of Medicine, Amarillo; Ronald Marino, M.D., chief, division of general pediatrics, NYU Winthrop Hospital, Mineola, N.Y.; April 9, 2018, Obstetrics and Gynecology, Abstract/Full Text (subscription or payment may be required)

Read more about what women should eat and drink—or avoid—while breast-feeding from the Academy of Nutrition and Dietetics.

Related Stories

Recent study in Oregon reveals public considers alcohol more harmful than marijuana

February 7, 2018
As the national conversation about marijuana legalization continues, an important question is how changing marijuana policy may influence use of other substances, such as alcohol. A new study, led by researchers at RTI International, ...

Maternal pot use under microscope in Colorado

February 3, 2015
Marijuana use by pregnant or nursing women might seem like a no-brainer of a bad idea, but a proposal in the state of Colorado to step up such warnings is raising concern because of limited research on the dangers.

Marijuana use higher in pregnant teens than nonpregnant peers

April 18, 2017
(HealthDay)—More than twice as many pregnant 12- to 17-year-olds use marijuana as their nonpregnant peers, and significantly more use the drug than pregnant women in their 20s, according to a letter published online April ...

Bill to make medical marijuana available in Malta proposed

November 20, 2017
Malta's government has proposed allowing all doctors in the country to prescribe medical marijuana.

Breast feeding okay for mothers taking immunosuppressant drug

January 24, 2013
Women taking the immunosuppressant tacrolimus can rest assured that breast feeding will not elevate their babies' exposure to the drug, according to a study appearing in an upcoming issue of the Clinical Journal of the American ...

Recommended for you

Though most prolapse surgeries regress over time, symptoms remain improved

April 17, 2018
An estimated one in three women in the U.S. has a pelvic floor disorder, a condition that often develops after bearing children and getting older. These disorders can lead to incontinence, painful intercourse and even the ...

Painkillers in pregnancy may affect baby's future fertility

April 16, 2018
Taking painkillers during pregnancy could affect the fertility of the unborn child in later life, research suggests.

Mom's marijuana winds up in breast milk

April 10, 2018
(HealthDay)—Breast-feeding has known benefits for both baby and mom, but if a new mom also smokes marijuana, does the drug turn up in her breast milk?

Like babies, eggs send signals when 'hungry'

April 9, 2018
In humans and other mammals, the female reproductive cells - the eggs or oocytes - need nourishment in order to grow and remain fertile. It is known that the egg gets its food from little arm-like feeding tubes (called filopodia) ...

New clues to restoring fertility in women with disabling ovary disorder

April 9, 2018
Groundbreaking research out of the University of Otago is showing potential to restore fertility in women suffering polycystic ovary syndrome.

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.